SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60bc02344009798feddf600ac9f4e80fa11250fa88ebddda0f3a7efa8e9d3a9b' 
  AND token = 'nWmEEb6e+gbktgNNXuCsFs91FstAXCk5WlBwva0/GkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}